How does a fog machine work?
Many theatrical performances, rock concerts and of course crime thriller recordings really come into their own. when a fog veils apparently important things or at least a strange mood arises leaves. How does the fog machine used work?
Fog machine - this is how it works
One way to create fog yourself in everyday life is to exhale in winter temperatures. The inhaled air warmed up in the lungs and sucked in water vapor. When it comes into contact with the cold outside air again, it releases its excess of water vapor as tiny condensed droplets. The fog machine works in a similar way:
- So-called Evaporator mist machines make use of this principle. The fog fluid, usually a mixture of water and glycols, a group of volatile alcohols, is heated and then ejected.
- The gas mixture condenses in the air and creates the enveloping mist. The fog machine sucks in the fluid in small quantities and feeds it to a preheated element. The mixture is already gaseous at the outlet nozzle and has a temperature of around 300 ° C.
- Fog can also be created on stage with liquid nitrogen. It is so cold that it can freeze the water vapor in the air. However, handling at -200 ° C is more complex. In earlier years dry ice, i.e. frozen carbon dioxide, with a temperature of -70 ° C was used to generate fog. Since the carbon dioxide is heavier than air, the fog created wafts particularly nicely on the ground. However, if the actors inhale too much of it, the gas makes you tired.
By the way: Even in ancient Greece, theater people used thermal fogging. They heated oil in a pan and turned it into a gaseous state. The oil gas rose and condensed into small droplets in the colder air.
In order for the next party to be really successful, you should have a fog machine ...
Veil of mist in the bottle - a separate experiment
The following experiment can be used to create fog in a bottle, true to the principle of how a real fog machine works:
- You need a transparent bottle or a glass flask and a suitable cap with a tube attachment. For this purpose, you can use a liqueur pourer or a rubber stopper with a bushing, such as is used for wine fermentation.
- Attach a short piece of flexible rubber hose to this spout.
- Now fill your bottle with some water and close it with the neck.
- Now suck some air out of the bottle with the help of the hose. Then clamp off the hose so that the resulting negative pressure is maintained in the bottle. Use metal pliers, a clamp, or just your fingers.
- A helper holds a lit match or a candle flame in front of the opening while you briefly open the clamp.
- Then blow hard into the hose and clamp it shut again.
- Shake the bottle vigorously a few times. When the hose is opened, clearly visible clouds of mist appear in the bottle. In this case, the exhaust gases from the flame are the condensation nuclei for the fine mist droplets.
